The best soil for growing tomatoes — experts share the secret to the perfect soil mix that will help yours thrive

Red, delicious, and easy to grow... if you do your homework on the best soil for growing tomatoes, that is.

Yes, there’s a reason so many beginners learn how to grow tomatoes as their very first crop; they're one of the easiest vegetables (fine, fruits) around.

That being said, there's so much more to successfully growing bright red tomatoes than sowing seeds or repotting tomato seedlings in any old dirt and hoping for the best. That's why it's important to pay attention to the pros and ensure you pick the very best soil for the job.

'Growing tomatoes is such a satisfying thing to do and they can be grown outside, undercover, in pots or even hanging baskets so everyone can grow them,' says Morris Hankinson, director of Hopes Grove Nurseries.

Morris Hankinson

Morris Hankinson is the founder and managing director of Hopes Grove Nurseries Ltd, the UK’s only specialist grower-retailer of hedging plants, which he established after graduating with a Commercial Horticulture Degree from Writtle College, Essex in 1992.

That being said, though, he agrees that you need to spend some time perfecting the soil if you want envy-inducing toms – whether that's testing your soil’s pH, learning how to test for nutrient deficiencies in your soil, or simply... well, simply knowing your soil type and how to improve it.

'Tomatoes need a well-drained, fertile soil which has been prepared by forking in lots of well-rotted organic matter if growing outside in the ground,' he explains.

'This will help to ensure the soil retains moisture but drains well by improving the structure and giving a boost of nutrients as well.'

Morris adds that 'tomatoes growing in pots will need good drainage again so make sure the pots have drainage holes and plant into a good quality peat free compost which will be enough for the entire season, with some extra feed as needed.'

If you really want the best soil for growing tomatoes, then, try something like Peat-Free Tomato Compost with added John Innes 60L from Amazon, as it comes with six months of feed blended into it.

Of course, you can get a little more technical about things if you prefer. 'For the best tomato growth, I suggest that you use rich, well-draining loamy soil with a pH of 6.0 to 6.8,' says Andrew O'Donoghue, one of the directors of Gardens Revived.

Andrew O'Donoghue

RHS-trained gardener Andrew O'Donoghue set up Gardens Revived with his brother, Christopher, in 2018 to create a thriving family business. Together, they have worked on residential gardens, listed buildings and gardens, flower shows and large estates with some exceeding 70 acres – many with historical significance.

How to improve soil for growing tomatoes

To ensure you have the best soil for growing tomatoes, Andrew and Morris go on to suggest you take care to do the following...

1. Add compost

'It's always a good idea to add compost or well-rotted manure for nutrients and perlite or sand to improve drainage,' says Andrew.

You can pick up a bag of Gro-Sure Perlite from Amazon easily enough if you want to do the latter.

2. Balance things out

The best soil for growing tomatoes will be very nutrient dense, which is why it's a good idea to spend some time conditioning yours ahead of planting.

'You can balance nutrients with phosphorus (bone meal), potassium (wood ash), and calcium (eggshells or gypsum) to prevent deficiencies,' says Andrew.

'Avoid excessive nitrogen, which promotes leaves over fruit.'

3. Get mulching

If you want happy tomatoes, Andrew suggests you take care to mulch with straw or compost to retain moisture and regulate temperature.

'This will help to keep the soil moist, as well as stop weeds from growing and protect your fruits from any soil-based diseases.'

4. Feed, feed, feed

Whether you have the best soil for growing tomatoes or not, it's worth remembering that they are hungry little fruits.

'Tomatoes do love a feed! By applying a balanced flow releasing fertiliser when first planted and then a high potassium fertiliser every one to two weeks when the fruit sets,' says Morris.

Using something like Levington Tomorite Organic Liquid Tomato Feed with Seaweed Extract (available from Amazon) will ensure strong growth and plenty of tomatoes to harvest.

5. And don't forget the water

As mentioned already, the best soil for growing tomatoes is one that drains well and that's because tomatoes are thirsty plants... even if they hate to get their feet wet.

'Maintain watering regularly, keeping the soil moist but not overwatered,' says Morris.

What is the best soil mix for tomatoes?

The best soil mix for tomatoes is one that is well-draining and nitrogen-rich. This means that you will need to dig in organic matter or a good peat-free compost, as well as keep them well fed with a high potassium fertiliser.

You should also consider mixing in bone meal or crushed eggshells – and don't forget to mulch!

What compost is best for tomatoes?

Tomatoes prefer things loamy and nutrient-dense, so something like a peat-free loam-based or multi-purpose compost is best. We recommend a John Innes No 2 compost (peat-free).

Now that you know the best soil for growing tomatoes, you can set to work filling your Mediterranean garden with these delicious red fruits.

Just be sure to spend some time researching the best pasta sauces and salad recipes, so you can use them up when you have a glut ready for harvesting!